Health insurance was a better predictor of survival from health attacks and strokes than race, according to Johns Hopkins researchers who looked at health outcomes in some Maryland hospitals.

Specifically, those who did not have coverage were more likely to die in the hospital, even after accounting for race and socioeconomic factors, according to the researchers at the Hopkins Bloomberg School of Public Health.

“African Americans living in poor, urban neighborhoods bear a high burden of illnesses and early death, from cardiovascular disease in particular,” said Derek Ng, lead author of the study and graduate student in the department of epidemiology, in a statement. “Our findings suggested that a lack of health insurance, or being under-insured, is a major cause of insufficient treatment and subsequent premature death.”

The study, published online in the Journal of General Internal Medicine, looked at 13,000 patients form three Maryland hospitals treating patients of all income levels. Those uninsured had a 31 percent higher risk of early death after a heart attack and a 50 percent higher risk after atherosclerosis than those with private insurance.

The researchers said as more people become insured under federal health care reform there needs efforts are needed to look more closely at the factors that could explain the disparities.